TIME 100 2015 Jennifer Doudna and Emmannuelle Charpentier
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Emmanuelle Charpentier & Jennifer Doudna

Apr 15, 2015

No one, not even a bacterium, likes being infected by a virus, and early in evolution, bacteria developed a way to destroy viruses with exquisitely precise attacks. Very recently, Emmanuelle Charpentier and Jennifer Doudna figured out the inner workings of this bacterial self-protection, and then, in a tour de force of elegant deduction and experiment, they developed a plug-and-play version of that approach. Their technique, CRISPR-Cas9, gives scientists the power to remove or add genetic material at will. Working with cells in a lab, geneticists have used this technology to cut out HIV, to correct sickle-cell anemia and to alter cancer cells to make them more susceptible to chemotherapy. With CRISPR-Cas9, a scientist could, in theory, alter any human gene. This is a true breakthrough, the implications of which we are just beginning to imagine.

King is a geneticist and the discoverer of the BRCA1 cancer gene

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